Selective magazine pencil



Feb. 23, 1937. w. DURRLER SELECTIVE MAGAZINE PENCIL Filed May 25, 1936 Hy- W/ b l lllllll ll lll Patented Feb. 23, 1937 UNITED STATES PATENT OFFICE Application May 25,

1936, Serial No. 813694 Germany May 31, 1935 4 Claims.

Selective magazine pencils are known, in which each of the lead holders slidable in a metal case and acted upon by a spring for the purpose of automatically bringing them into their operative and inoperative positions is provided wth a pushknob whch projects through a slot in the metal case. In these known pencils the lead holders are shifted from the inoperative into the position for use by placing a finger or preferably the thumb on the push knob, and they spring back automatically into their inoperative position when the push knob is disengaged from a catch or pressed inwards.

These known selective lead magazine pencils are open to the objection that the lead holder when pushed into the position ready for use often springs back owing to accidental disengagement of the locking means by placing the finger on the push and catch knobs projecting from the case when writing. The cost of production of these pencils is considerably increased by employing push knobs and their complicated fixing means. A great objection is also that foreign bodies can pass through the guide slots and cause failure of the pushing mechanism.

All these objections are overcome by the invention according to which the lead holders in the inner sleeve provided with guide slots and rotatable in the pencil case are controlled by pressure springs and have guide pins projecting through the slots in the inner sleeve and bearing against a. tube fixed in the pencil case and provided with an ascending peripheral camface and a drop edge so that, when theinner sleeve is rotated, the pins run onthe edge of the cam at certain distances apart according to their position, and finally on reaching the drop edge slide along the same into the beginning position of the cam arid the lead holders spring into their position for writing. v

Two embodiments of the invention are illustrated by way of example in the accompanying drawing, in which:-

Fig. 1 shows'the selective magazine pencil in elevation, the case shown in longitudinal section.

Fig. 2 is a cross section on line 2-2 of Fig. 1.

Fig. 3 shows the pencil in longitudinalsection.

Fig. 4 shows the metal guide tube in developed state with the lead holders in position thereon.

Fig. 5 shows in elevation a lead holder of modifled construction.

An inner sleeve d provided with a plurality of slots corresponding to the number of ,lead holders 1: is rotatably mounted in a metal case a. 55 This sleeve d has on its rear end projecting from the metal case a a cap e serving as knob for turning the inner sleeve. In order to prevent the inner sleeve (1 from being pulled out of the metal case a. two tube lengths f and g are slipped on the inner sleeve (2, the tube length 1 being fixed on the inner sleeve (1 and the tube length a on the pencil case a. The lead holders b are acted upon by pressure springs 71, and separately guided therewith in tubes 2' having slots k registering with the slots 0 in the inner sleeve d, so that guide pins m fixed on the lead holders I) extend through both slots k and 0..

A tube length n is fixed in the front portion of the pencil case a and has on its rear end an ascending circumferential cam face 0 and a vertical drop edge p leading to the beginning of the cam face 0. The guide pins m of the lead holders b bear at uniform distances apart on the cam face 0 and ride up this cam 0 when the inner sleeve d is rotated relatively to the pencil case by means of the knob e, each guide pin m on reaching the drop edge p jumps into its positionat the beginning of the cam face 0 under the action of its spring h and brings its lead holder into the position for writing.

In order to prevent the accidental retraction of the lead holder b which is in writing position whilst the pencil is in use, the guidepin m of the holder engages in a notch q at the beginning of the cam face 0.

For the purpose of locking the-lead holders b in a position in which none of therrf "in position for writing (Fig. .4) the uppermos .guide'pin m snaps into a notch r at the upper extremity of the cam face 0 directly adjacent the drop face 1) before descending. By specially shaping the lead holders b, which are provided with a bent intermediate piece In made of wire (Fig. the movability of the lead holders b is increasedland they slide more accurately to the outlet oint of the pencil case a.

The space t separated from the inner sleeve (1 by a partition s serves for accommodating spare .leads.

The present invention not only enables the lead holders 1) to be quickly changed, 'but ornaments on the exterior of the pencil casea are no longer interrupted by unsightly slots and push knobs.

I claim:-

1. A selective magazine pencil; comprising in combination an outer case, a set of parallel guide tubes in said case each tube having a longitudinal guide slot, a plurality of lead holders one longitudinally slidable in each of said tubes, a spiral cam element with a single turn rotatable 55 in said case and concentrically surrounding said set of guide tubes, said cam element having a cam face ascending towards the rear end of the pencil with a drop edge at its end leading to the beginning point, guide pins one on the rear end of each of said lead holders and each projecting through the slot in its guide tube and bearing against said cam face, and springs one in each of said tubes and adapted to automatically press said holders into operative position as the guide pins reach the drop edge of said cam element.

2. A selective magazine pencil, comprising in combination an outer case, a set of parallel guide tubes in said case each tube having a longitudinal guide slot, a plurality of lead holders one longitudinally slidable in each of said tubes, a spiral cam element with a single turn rotatable in said case and concentrically surrounding said set of guide tubes, said cam element have a cam face ascending towards the rear end of the pencil with a drop edge at its end leading to the beginning point, guide pins one on the rear end of each of said lead holders and each projecting through the slot in its guide tube and bearing against said cam face, springs one in each of said tubes and adapted to automatically press said holders into operative position as the guide pins reach the drop edge of said cam element, said cam face having at its upper extremity a notch adapted to receive said guide pins to lock the uppermost of said pins in its extreme retracted position to prevent the same from accidentally jumping into operative position under the action of its spring.

3. A selective magazine pencil, comprising in combination an outer case, a set of parallel guide tubes in said case each tube having a longitudinal guide slot, a plurality of lead holders one longitudinally slidable in each of said tubes, a spiral cam element with a single turn rotatable in said case and concentrically surrounding said set of guide tubes, said cam element having a cam face ascending towards the rear end of the pencil with a drop edge at its end leading to the beginning point, guide pins one on the rear end of each of said lead holders and each projecting through the slot in its guide tube and bearing against said cam face, springs one in each of said tubes and adapted to automatically press said holders into operative position as the guide pins reach the drop edge of said cam element, said cam element having a notch in its drop face directly adjacent the beginning of said cam face, said notch adapted to receive said pins to lock the foremost of said holders in its operative position and prevent the same accidentally receding under the pressure exerted when writing.

4. A selective magazine pencil, comprising in combination an outer case, a set of parallel guide tubes in said case each tube having a longitudinal guide slot, a plurality of lead holders one longitudinally slidable in each of said tubes, a spiral cam element with a single turn rotatable in said case and concentrically surrounding said set of guide tubes, said cam element having a cam face ascending towards the rear end of the pencil with a drop edge at its end leading to the beginning point, guide pins one on the rear end of each of said lead holders and each projecting through the slot in its guide tube and bearing against said cam face, springs one in each of said tubes and adapted to automatically press said holders into operative position as the guide pins reach the drop edge of said cam element, said cam face having at its upper extremity a notch. adapted to receive said guide pins to lock the uppermost of said pins in its extreme retracted position to pre vent the same from accidentally jumping into operative position under the action of its spring, said cam element having a notch in its drop face directly adjacent the beginning of said cam face, said notch adapted to receive said pins to lock the foremost of said holders in its operative position and prevent the same accidentally receding under the pressure exerted when writing.

WILHELM nimmlna. 

